BabylonJS/Babylon.js · error

Pass "${pass.name}" is not valid. ${errMsg}

Error message

Pass "${pass.name}" is not valid. ${errMsg}

What it means

FrameGraphTask._checkTask() validates each pass created by a task's record() by calling pass._isValid(); if a pass reports an error message, the task throws during frameGraph.build(). This instance validates the ENABLED passes list, typically reporting missing/invalid render targets or unset required pass properties.

Source

Thrown at packages/dev/core/src/FrameGraph/frameGraphTask.ts:168

    /** @internal */
    public _addPass(pass: IFrameGraphPass, disabled: boolean) {
        if (disabled) {
            this._passesDisabled.push(pass);
        } else {
            this._passes.push(pass);
        }
    }

    /** @internal */
    public _checkTask() {
        let outputTexture: Nullable<Nullable<InternalTexture>[]> = null;
        let outputDepthTexture: Nullable<InternalTexture> = null;
        let outputObjectList: FrameGraphObjectList | undefined;

        for (const pass of this._passes) {
            const errMsg = pass._isValid();
            if (errMsg) {
                throw new Error(`Pass "${pass.name}" is not valid. ${errMsg}`);
            }
            if (FrameGraphRenderPass.IsRenderPass(pass)) {
                const handles = Array.isArray(pass.renderTarget) ? pass.renderTarget : [pass.renderTarget];
                outputTexture = [];
                for (const handle of handles) {
                    if (handle !== undefined) {
                        outputTexture.push(this._frameGraph.textureManager.getTextureFromHandle(handle));
                    }
                }
                outputDepthTexture = pass.renderTargetDepth !== undefined ? this._frameGraph.textureManager.getTextureFromHandle(pass.renderTargetDepth) : null;
            } else if (FrameGraphObjectListPass.IsObjectListPass(pass)) {
                outputObjectList = pass.objectList;
            }
        }

        let disabledOutputTexture: Nullable<Nullable<InternalTexture>[]> = null;
        let disabledOutputTextureHandle: (FrameGraphTextureHandle | undefined)[] = [];
        let disabledOutputDepthTexture: Nullable<InternalTexture> = null;

View on GitHub (pinned to 0592b347b8)

Solutions

1. Read errMsg in the thrown message to identify which pass and what check failed.
2. Set pass.renderTarget (via pass.setRenderTarget) to valid texture handles in your task's record().
3. Ensure all of the task's texture inputs are assigned before build() so passes resolve valid handles.
4. Implement/fix _isValid() in custom pass subclasses so it returns null when the pass is fully configured.

Example fix

// before
public record() {
  const pass = this._frameGraph.addRenderPass(this.name);
  // renderTarget never set -> _isValid() fails
}
// after
public record() {
  const pass = this._frameGraph.addRenderPass(this.name);
  pass.setRenderTarget(this.targetTexture);
  pass.setExecuteFunc((ctx) => { /* ... */ });
}

// before build(), ensure every enabled pass of each task has a render target
for (const task of tasks) {
  for (const pass of task._passes) {
    if (FrameGraphRenderPass.IsRenderPass(pass) && pass.renderTarget === undefined) {
      throw new Error(`Pass ${pass.name} has no render target`);
    }
  }
}

try {
  frameGraph.build();
} catch (e) {
  const m = String(e.message).match(/Pass "(.+)" is not valid\. (.+)/);
  if (m) {
    console.error(`Fix pass ${m[1]}: ${m[2]}`);
  } else {
    throw e;
  }
}

When it happens

Trigger: Calling frameGraph.build() where a task's main (enabled) pass _isValid() returns a non-empty error — e.g. a render pass with an undefined renderTarget, a pass referencing a texture handle that can't be resolved, or a pass lacking an execute function setup.

Common situations: Custom tasks creating passes without setting renderTarget; tasks whose input texture assignments were forgotten so their passes hold undefined handles; a pass whose dependency texture was removed during graph refactoring.

Related errors

• FrameGraphClearTextureTask ${this.name}: the depth texture (
• FrameGraphCopyToBackbufferColorTask "${this.name}": sourceTe
• FrameGraphCopyToTextureTask "${this.name}": sourceTexture an
• FrameGraphGenerateMipMapsTask ${this.name}: targetTexture is
• FrameGraphGenerateMipMapsTask ${this.name}: targetTexture mu

AI-assisted analysis of BabylonJS/Babylon.js@0592b347b8 (2026-08-30). Data as JSON: /api/errors/0b6873ef9d28ac72. Report an issue: GitHub.